Muscle tissue

Question 1

What are the dimensions of skeletal muscle fibres?

Answer 1

Diameter: ~10-100 µm

Length: 1mm - 0.5m

Question 2

What is the arrangement of skeletal muscle support tissue?

Answer 2

• Endomysium: Inward projections of connective tissue from the perimysium to surround indiviudal muscle fibres.
• Perimysium: Connective tissue covering each fascicle.
• Epimysium: Connective tissue layer covering each muscle.

Question 3

What are the different types of skeletal muscle fibres?

Answer 3

1. Type 1 fibres: Red, aerobic and slow-twitch
2. Type 2 fibres: White, anaerobic and fast-twitch
3. Intermediate fibres

Question 4

What type of tissues areskeletal muscle tendons?

Answer 4

Connective tissues

Question 5

What are the dimensions of a cardiac muscle cell?

Answer 5

Diameter: 15 µm

Length: 100 µm

Question 6

What are the structural features in cardiac muscle interculated discs?

Answer 6

1. Intermediate junctions: Anchors actin filaments between cells and allows mechanical coupling of contraction.
2. Desmosomes: Physically sticks the cardiac muscle cells together.
3. Gap junctions: Electrical synapse allowing direct conduction of APs from one muscle cell to another. This makes myocardium an electrical syncytium.

Question 7

What are the different types of smooth muscle?

Answer 7

1. Single-unit: Smooth muscle cells are electrically coupled to each other and operate as electrical syncytium.
2. Muli-unit: Cells function as individuals.

Question 8

What are the dimensions of smooth muscles?

Answer 8

Diameter: 5-10 µm

Length: 20-200 µm